Tex. Const. art. V, § 4

(a) The Court of Criminal Appeals shall consist of eight Judges and one Presiding Judge. The Judges shall have the same qualifications and receive the same salaries as the Associate Justices of the Supreme Court, and the Presiding Judge shall have the same qualifications and receive the same salary as the Chief Justice of the Supreme Court. The Presiding Judge and the Judges shall be elected by the qualified voters of the state at a general election and shall hold their offices for a term of six years.

(b) For the purpose of hearing cases, the Court of Criminal Appeals may sit in panels of three Judges, the designation thereof to be under rules established by the court. In a panel of three Judges, two Judges shall constitute a quorum and the concurrence of two Judges shall be necessary for a decision. The Presiding Judge, under rules established by the court, shall convene the court en banc for the transaction of all other business and may convene the court en banc for the purpose of hearing cases. The court must sit en banc during proceedings involving capital punishment and other cases as required by law. When convened en banc, five Judges shall constitute a quorum and the concurrence of five Judges shall be necessary for a decision. The Court of Criminal Appeals may appoint Commissioners in aid of the Court of Criminal Appeals as provided by law.